As smog leads to coal bans in China’s eastern cities the industry is heading to its wildernesses, with potentially significant impacts.

Here, 4,000 metres above sea level coal mining is threatening the water supply to the the regions rivers, with possible knock on effects for the over 50 cities and 420 towns that rely on the Yellow River – China’s second longest – for their drinking water and thousands who use it to irrigate their fields.

After an undercover investigation by Greenpeace local officials have confirmed illegal mining projects are taking place in a nature reserve and environmental regulations have been breached.